Search Results

Search found 35571 results on 1423 pages for 'sql developer'.

Page 950/1423 | < Previous Page | 946 947 948 949 950 951 952 953 954 955 956 957  | Next Page >

  • Adding gcc 4.9 as a compiler option in Xcode

    - by user2129150
    I asked this question on StackOverflow, but it's pretty much stagnant. Sorry if this is considered a repost/double-post. I just installed gcc 4.9 (with C11 support), and want to add it to Xcode 4.6.3's build options as a compiler option. I ran make and make install, and the packages are all there (under /usr/bin/gcc. Running gcc --version confirms that gcc 4.9 is installed rather than an older version. When I go into an existing Xcode project's build settings, the only compiler options available are Apple LLVM compiler 4.2 LLVM GCC 4.2 Other... Clearly, GCC 4.9 would have to be added using the "Other..." option, although I'm not sure how. I've tried inputting the path to gcc (/usr/bin/gcc), although the default value for other isn't a path at all: com.apple.compilers.llvmgcc42. I've also tried following the instructions from the answer to this question as well, but the machine I'm on doesn't have the /Developer directory at all, since I believe Apple integrated the developer tools that required (and created) this directory into Xcode. How do I add gcc 4.9 as a compiler option in Xcode?

    Read the article

  • How do I install git/git-svn on RHEL5 with a custom perl install?

    - by kbosak
    I've had nothing but trouble trying to install Git on RHEL5. First I tried from source, but ran into several issues with installing the docs. There appeared to be missing libs and such for parsing xml that I couldn't figure out how to get installed and recognized. Then I tried using the EPEL yum repository and was able to install git and its docs but now git-svn is not working. It complains about not finding the perl modules Git.pm and SVN/Core.pm. When I set the GITPERLLIB environment variable to the location of those libs it seg faults. Some background: RHEL5 came with perl 5.8.8, but we wanted to use 5.10 so I installed that from source (to a custom location). Someone then symlinked the system perl binary to this newer version of Perl to make sure nobody uses the wrong version. Each developer also has their own build of Perl. So I'm wondering what's the best way to install Git on this system and have both the docs and git-svn working correctly for each user. Unfortunately I'm a developer and not as good with system administration so take it easy on me.

    Read the article

  • Windows Server 2012 Hyper-V very slow

    - by Matt Taylor
    I have been running several Hyper-V VMs on Windows Server 2008 R2 for the past couple of years and enjoying perfectly adequate performance for my testing/development/r&d environments. I'm a software developer so my hardware knowledge is basic however I built the rig using: •Gigabyte GA-X58A-UD3R Intel X58 (Socket 1366) DDR3 Motherboard •Intel Core i7 960 3.20GHz (Bloomfield) (Socket LGA1366) •24GB triple channel RAM The host OS is running on an OCZ SSD and all the VMs are running on a 2TB Marvell SATA3 RAID 0 array consisting of 2 Western Digital Caviar Black 7,200rpm drives. I have tested the speed of the 2TB drive and appear to be getting less than 3Mbs but it can adequately run a 4 VM farm including a DC, (SQL) database and IIS application servers. I recently upgraded the SSD on which the host runs to a 256GB OCZ Vertex 4 and took the opportunity to upgrade to Windows Server 2012 and installed the Hyper-V role. I tried importing one of my existing Windows Server 2008 R2 VMs (and converted it to .vhdx) plus I have tried creating a brand new Windows Server 2008 R2 VM but both are running extremely slowly and I can see nothing obvious using the host and guest Task Manager/Resource Monitor tools. In both cases the VM has 8GB RAM (fixed), 4 CPUs, fixed size HD (not expanding) and is using an external virtual network running on a separate NIC to the host. I have upgraded the BIOS to the latest available version and checked the virtualization settings. I have run out of "obvious" (to a developer) things to check/configure and my next option will be to re-install the host OS but before I do I would very much appreciate any advice from any experts out there. Thanks

    Read the article

  • Custom Extensions on Managed Chromebooks

    - by user417669
    I am a developer looking for the best way to set up different schools with their own custom, private extensions (ie School A should be the only one with access to Extension A). Theoretically, I am aware that there are a few ways to get a custom, private extension pushed out on a domain: Host the .crx on a server and click "Specify a Custom App" in the management console. Create a Domain App by uploading a zip to the Chrome Web Store Upload the extension from my developer account to the Chrome Web Store and publish to a single "trusted tester," or make it unlisted Option (1), hosting the .crx, has not been working. I am not sure why, but the extension is simply not pushing out. I link directly to the crx file, which has the right ID and MIME type, still, no dice. If anyone has any tips or suggestions for getting this to work, I would love to hear them! Option (2), having the school create a domain app, seems a bit inefficient because it requires all schools to upload their own zip. So essentially I would have to email a zip file to the school, and have them publish it. All updates to the extension will also require a similar process, so this doesn't seem ideal. I doubt that option (3) would work. If I published to the admin as a "trusted tester", I don't think that the other people in the domain would be able to access it. If it is unlisted, I do not know how an admin could find it in the Chrome Web Store dialog. Also, I would rather avoid security through obscurity. Has anyone had success with hosting the extension and using the Specify a Custom App feature? Any other suggestions for getting a Custom Extension pushed out by the management console? Thanks so much!

    Read the article

  • OS X superuser folders automatically created. Perusers launchd process appears to kill 501

    - by Ric Pen
    New Apple laptop OSX 10.8.2. I have used OS X but many years previously, and am not familiar with subtleties or changes in com.apple.launchd.peruser.x... I have previously (and in retrospect, foolishly) made changes to these rapidly spawned new peruser accounts (my initial reaction was that if ipfw was disabled, then I might well be under hacker attack, which I have dealt with, years ago), but I believe I was wrong, and the results of my efforts at preserving the system's integrity have in fact been destructive, overreactive, and have resulted in much work to restore. My understanding from other posts is that superuser protocols have changed quite dramatically since I bought the first developer version of OS X many years ago. Haven't developed on Apple much since then, w/ exception of WebObjects (IMO, much underrated at that time, and was more user friendly than ASP (prior to .NET, I vaguely recall). Creation of apparently nasty peruser folders appear to confound 501 process, which logs inability to find firewall (ipfw). Can someone help me with this? I am concerned that either the system is improperly configured, an application was improperly installed (although there is little here beyond Apple's SDK, which I find quite accommodating and intuitive). Still, I am a novice, only sporadically develop at this time, and would really just like to see this system running happily. Please offer assistance, in the form of potential info sources, or if you have had a similar experience, then perhaps scripts to suss out this issue. I do not wish to damage the system, but Apple's Developer connection and discussion threads do not appear to have dealt with this particular issue recently... Although I may well have missed something you have not - please apprise. Any assistance on this issue is very much appreciated - by an old guy, who wants to do some things which were fun about 20 years ago.

    Read the article

  • Virus on site but can't find where

    - by Rob
    WARNING! THIS IS ABOUT A VIRUS ON MY SITE. IT APPEARS IT HAS BEEN THERE FOR SOMETIME AND I'VE HAD NO PROBLEMS. BUT PLEASE BE CAREFUL. READ EVERYTHING I SAY AND SEE IF YOU CAN HELP ME WITHOUT VISITING THE LINK. AVG PICKS UP ON IT AND BLOCKS IT, MCAFEE DOES NOT. Sorry about the warning, obviously i'm not here to get anyone infected or anything like that. Basically I run the website sortitoutsi dot net. Ages ago I got a virus on my computer, they got hold of my FTP passwords and added some lines of javascript to the top of my site. I removed them and believe it was fixed. However i'm using the "Web Developer" extension for Firefox and chose to view all javascript on my page and find there are various links to horrible urls such as: gittigidiyor-com.excite.co.jp.webmasterworld-com.eastmusicdirect.ru:8080/aboutus.org/aboutus.org/google.com/skycn.com/torrents.ru.php and gittigidiyor-com.excite.co.jp.webmasterworld-com.eastmusicdirect.ru:8080/index.php?jl= These terms do not appear anywhere. In the source code, in any of the javascript or the css. I also can't see that there are any rogue images that I don't recognise either. So i've no idea where this javascript is coming from. Can anyone suggest how I can find references to these links and remove them? I can see them both in the Web Developer firefox extension and in the net tab using Firebug. Any help would be greatly appreciated

    Read the article

  • Windows 7 starts getting sluggish over a few days

    - by munrobasher
    Myself and the other developer are running Windows 7 Enterprise 64 bit with 8GB RAM on different Gigabyte motherboards with Quad core Intel CPUs. Most of the time, it runs like a dream. We use VMware workstation a lot (hence the 8GB) and that works well. Except... now and then, after the PCs have been on for a few days, the whole system starts getting really sluggish doing certain tasks. The other's developer's system is far worse than mine with it taking up to a minute to launch IE. Today, mine has gone sluggish but nowhere near as bad. For example, normally when I click on a new tab in IE, it's instant. Today, there's an obvious delay. Right-clicking in this window to trigger iSpell is normally instant, right now it takes about five seconds. I've got resource monitor open on my second monitor and when I did that right-click, there was no obvious peak in CPU, disk or memory. A reboot does fix it so it does sound like a resource issue but haven't a clue what might be to blame. The two computers have similarities (same spec) but also differences (like motherboard, RAM & CPU models). So I guess the question is, any pointers on diagnosing why a PC is sluggish? What could cause such a right-click slow down in IE for example? It sounds like such a simple operation. NOTE: whilst typing this message alone, it was fine performance wise. I can click around the page no problem but right-click still is noticeable slow. Will reboot over lunch... Cheers, Rob.

    Read the article

  • Office 2010 Trust Center settings: How to enable data connections in the "old" way?

    - by GSerg
    We're planning an upgrade Office 2003 - 2010 and have identified a big problem. In Office 2003, if the workbook you're opening contains a query table that fetches data from a data source automatically (upon file open or in certain intervals), then a security dialog pops up - whether you want to allow that. If you say Yes, the queries will refresh automatically when they need to. If you say No, the queries will not refresh automatically, neither on file open nor on time intervals, but you will be able to refresh any of them manually at any time by right-clicking and selecting Refresh. There is also a registry parameter to say, Don't display that dialog, just allow the queries. This is exactly what we want. On users' computers we have the registry parameter applied, so the users never see any dialogs. On developers' computers the parameter is not applied, so every time a file is opened the developer decides whether to allow the auto-refreshing for the current session. Usually the answer is No, because for developing, it is essential to not have quieres refresh when they want to, but instead, refresh them when the developer wants. The problem is that in Office 2010 which we are testing we can't find a way to achieve this functionality: The allow/disallow messages are now grouped into one yellow button, that either allows everything or disallows everything (including, say, macros, if macro security is set to "Disable, but ask"). If you don't click the yellow Allow button, the queries are disabled completely, not just for automatic execution. You cannot right-click and refresh a particular query -- doing that would summon a security dialog prompting for enabling queries, and if you say Yes, all queries in the document will be enabled for auto-execution and will start executing immediately. This sort of ruins our development environment. Is there a way to get the trust thingies in Office 2010 to work in the same way as before? Is there a yet another registry parameter to say, Prompt for auto-refresh, but allow manual refresh even when auto-refresh is disabled?

    Read the article

  • Windows 7 PC freezes frequently with hard disk light constantly on

    - by Senthil
    I recently replaced a defective hard disk with a new one - Windows 7 - "A disk read error occured. Press Ctrl + Alt + Del to restart" I have been using the new hard disk with a Windows 7 installation for about 4 days. Now it has started freezing frequently. Sometimes every 2 minutes and sometimes every 10 seconds. There is lots of software installed - I am a developer and my PC is full of IDEs, database servers, web servers, developer tools, testing tools, all browsers etc.. My windows is up to date as of now. I have installed ALL updates including optional drivers etc. All my installed software is up to date. I scanned my computer using Microsoft Security Essentials and found nothing malicious. I did a chkdsk /r and found no problems. I did a memory diagnostic and found no problems. When I go into safe mode, it doesn't freeze and I am able to use it normally for longer periods of time. What other steps can I take to locate the problem?

    Read the article

  • Local user vs. domain user? What is the right way here?

    - by ebeeb
    I'm a software developer in a company with 6 employees. Everyone has a machine for him-/herself, so none of the machines is shared. I'm currently setting up my machine with Windows 8 and was experimenting a bit with domain and local user accounts. Correct me please if I'm wrong, but I think the idea behind is, that domain users generally should not be able to modify the configuration of a machine (like installing software), since they are able to login on every single machine in the domain. The local user (usually just one local administrator per machine) is the one who cares about the configuration of the machine. But in my case the login into the domain is just for being able to access directories/servers in the domain (I do not really know the details, all I know is, that loggin into the domain user account is necessary). So overall I've got a local admin account and a domain account used on my machine. While working I'm logged in to my domain user account. But it annoys me, that I always need to enter the credentials of my local user account when I'm about to update/install something, which happens quite often as a software developer. I fixed this with adding the domain account into the user accounts in my control panel and putting it into the Administrators group. The only thing I wanted to know about this: is there something REALLY bad about doing this? Or is there maybe a more common way to be able to act like a local admin, while logged in as a domain user? PS: I'm sorry about the tags, but I don't know the proper ones. I'd be glad if some of the superuser experts could fix this :-)

    Read the article

  • The Web Hosting Connundrum for "not quite" developers

    - by saltcod
    Hey all, Apologies if this post feels like its been covered elsewhere, but I don't think it has. I've been down a winding web hosting road. To date, I've tried: Joyent, Media Temple, Bluehost, Hostgator, and finally Linode. The reason for switching are likely obvious to everyone: speed. With the exception of the lightening fast Linode, all of the shared hosts are absolutely sloooow. What do do when you're not really a "developer" While I'v grown addicted to the speed of Linode, I really don't feel like its where I should be. I have this nagging feeling in the back of my mind that one of these days (likely soon), I'm going to run into something that i won't be able to figure out and i'll have days worth of downtime. Just the other day, for example, I realized that one of my domains wasn't sending emails. After 4(!) hours looking into the problem, I still can't get sendmail or postfix to work. Four hours!! I want to be a Drupal expert, not a Ubuntu expert That's really the heart of my problem: I spend way too much time learning Ubuntu's ins-and-outs, and not nearly enough time working on Drupal. So here goes: Is there a web host out there anywhere that offers the speed of Linode, but will let me focus on Drupal instead of sys-admin-ing? Thanks! [ I know, I know. There are going to be lots of people who read this saying - "just learn Ubuntu like a real developer". And I get that. I do. But when I work full-time and try and develop some of these sites in my evenings and weekends, I'm really feeling like the sys-admin stuff gets in the way.

    Read the article

  • AMD processors witn graphics card bundled [closed]

    - by shybovycha
    Sorry for posting this question here - just don't know to which StackExchange website i should be writing. I've heard AMD created processors with video card bundled. So now these processors should work as fast as just usual processors with discrete video card but AMD's ones should use less power and spread less warm. Some googling around gave me the result like "AMD processors of A-series". They were mentioned to be build using that technology i described above. But on the other hand, we have a small rate of publishing and not-very-good quality of AMD drivers. I am a game-developer and web-developer so i need a powerful processor and graphics card and a lot of RAM on board (to make it possible to create a sample Grails application, for example or to create some 3D models in Maya/Cinema4D, for instance). Still i want my battery to be a long-living one, so power usage is a bit critical for me. So, my questions are: are there any processor building technology like i've described and which series they are (if they exist)? which processor shall fit the laptop the best: AMD one or i5/i7 on with nVidia graphics card for the purposes mentioned above?

    Read the article

  • Tutorial: Criando um Componente para o UCM

    - by Denisd
    Então você já instalou o UCM, seguindo o tutorial: http://blogs.oracle.com/ecmbrasil/2009/05/tutorial_de_instalao_do_ucm.html e também já fez o hands-on: http://blogs.oracle.com/ecmbrasil/2009/10/tutorial_de_ucm.html e agora quer ir além do básico? Quer começar a criar funcionalidades para o UCM? Quer se tornar um desenvolvedor do UCM? Quer criar o Content Server à sua imagem e semelhança?! Pois hoje é o seu dia de sorte! Neste tutorial, iremos aprender a criar um componente para o Content Server. O nosso primeiro componente, embora não seja tão simples, será feito apenas com recursos do Content Server. Em um futuro tutorial, iremos aprender a usar classes java como parte de nossos componentes. Neste tutorial, vamos desenvolver um recurso de Favoritos, aonde os usuários poderão marcar determinados documentos como seus Favoritos, e depois consultar estes documentos em uma lista. Não iremos montar o componente com todas as suas funcionalidades, mas com o que vocês verão aqui, será tranquilo aprimorar este componente, inclusive para ambientes de produção. Componente MyFavorites Algumas características do nosso componente favoritos: - Por motivos de espaço, iremos montar este componente de uma forma “rápida e crua”, ou seja, sem seguir necessariamente as melhores práticas de desenvolvimento de componentes. Para entender melhor a prática de desenvolvimento de componentes, recomendo a leitura do guia Working With Components. - Ele será desenvolvido apenas para português-Brasil. Outros idiomas podem ser adicionados posteriormente. - Ele irá apresentar uma opção “Adicionar aos Favoritos” no menu “Content Actions” (tela Content Information), para que o usuário possa definir este arquivo como um dos seus favoritos. - Ao clicar neste link, o usuário será direcionado à uma tela aonde ele poderá digitar um comentário sobre este favorito, para facilitar a leitura depois. - Os favoritos ficarão salvos em uma tabela de banco de dados que iremos criar como parte do componente - A aba “My Content Server” terá uma opção nova chamada “Meus Favoritos”, que irá trazer uma tela que lista os favoritos, permitindo que o usuário possa deletar os links - Alguns recursos ficarão de fora deste exercício, novamente por motivos de espaço. Mas iremos listar estes recursos ao final, como exercícios complementares. Recursos do nosso Componente O componente Favoritos será desenvolvido com alguns recursos. Vamos conhecer melhor o que são estes recursos e quais são as suas funções: - Query: Uma query é qualquer atividade que eu preciso executar no banco, o famoso CRUD: Criar, Ler, Atualizar, Deletar. Existem diferentes jeitos de chamar a query, dependendo do propósito: Select Query: executa um comando SQL, mas descarta o resultado. Usado apenas para testar se a conexão com o banco está ok. Não será usado no nosso exercício. Execute Query: executa um comando SQL que altera informações do banco. Pode ser um INSERT, UPDATE ou DELETE. Descarta os resultados. Iremos usar Execute Query para criar, alterar e excluir os favoritos. Select Cache Query: executa um comando SQL SELECT e armazena os resultados em um ResultSet. Este ResultSet retorna como resultado do serviço e pode ser manipulado em IDOC, Java ou outras linguagens. Iremos utilizar Select Cache Query para retornar a lista de favoritos de um usuário. - Service: Os serviços são os responsáveis por executar as queries (ou classes java, mas isso é papo para um outro tutorial...). O serviço recebe os parâmetros de entrada, executa a query e retorna o ResultSet (no caso de um SELECT). Os serviços podem ser executados através de templates, páginas IDOC, outras aplicações (através de API), ou diretamente na URL do browser. Neste exercício criaremos serviços para Criar, Editar, Deletar e Listar os favoritos de um usuário. - Template: Os templates são as interfaces gráficas (páginas) que serão apresentadas aos usuários. Por exemplo, antes de executar o serviço que deleta um documento do favoritos, quero que o usuário veja uma tela com o ID do Documento e um botão Confirma, para que ele tenha certeza que está deletando o registro correto. Esta tela pode ser criada como um template. Neste exercício iremos construir templates para os principais serviços, além da página que lista todos os favoritos do usuário e apresenta as ações de editar e deletar. Os templates nada mais são do que páginas HTML com scripts IDOC. A nossa sequência de atividades para o desenvolvimento deste componente será: - Criar a Tabela do banco - Criar o componente usando o Component Wizard - Criar as Queries para inserir, editar, deletar e listar os favoritos - Criar os Serviços que executam estas Queries - Criar os templates, que são as páginas que irão interagir com os usuários - Criar os links, na página de informações do conteúdo e no painel My Content Server Pois bem, vamos começar! Confira este tutorial na íntegra clicando neste link: http://blogs.oracle.com/ecmbrasil/Tutorial_Componente_Banco.pdf   Happy coding!  :-)

    Read the article

  • Chart Control in ASP.Net 4 – Second Part

    - by sreejukg
      Couple of weeks before, I have written an introduction about the chart control available in .Net framework. In that article, I explained the basic usage of the chart control with a simple example. You can read that article from the url http://weblogs.asp.net/sreejukg/archive/2010/12/31/getting-started-with-chart-control-in-asp-net-4-0.aspx. In this article I am going to demonstrate how one can generate various types of charts that can be generated easily using the ASP.Net chart control. Let us recollect the data sample we were working in the previous sample. The following is the data I used in the previous article. id SaleAmount SalesPerson SaleType SaleDate CompletionStatus (%) 1 1000 Jack Development 2010-01-01 100 2 300 Mills Consultancy 2010-04-14 90 3 4000 Mills Development 2010-05-15 80 4 2500 Mike eMarketting 2010-06-15 40 5 1080 Jack Development 2010-07-15 30 6 6500 Mills Consultancy 2010-08-24 65 In this article I am going to demonstrate various graphical reports generated from this data with the help of chart control. The following are the reports I am going to generate 1. Representation of share of Sales by each Sales person. 2. Representation of share of sales data according to sale type 3. Representation of sales progress over time period I am going to demonstrate how to bind the chart control programmatically. In order to facilitate this, I created an aspx page named “SalesAnalysis.Aspx” to my project. In the page I added the following controls 1. Dropdownlist control – with id ddlAnalysisType, user will use this to choose the type of chart they want to see. 2. A Button control – with id btnSubmit , by clicking this button, the chart based on the dropdownlist selection will be shown to the user 3. A label Control – with id lblMessage, to display the message to the user, initially this will ask the user to select an option and click on the button. 4. Chart control – with id chrtAnalysis, by default, I set visible = false so that during the page load the chart will be hidden to the users. The following is the initial output of the page. Generating chart for salesperson share Now from Visual Studio, I have double clicked on the button; it created the event handler btnSubmit_Click. In the button Submit event handler, I am using a switch case to execute the corresponding SQL statement and bind it to the chart control. The below is the code for generating the sales person share chart using a pie chart. The above code produces the following output The steps for creating the above chart can be summarized as follows. You specify a chart area, then a series and bind the chart to some x and y values. That is it. If you want to control the chart size and position, you can set the properties for the ChartArea.Position element. For e.g. in the previous code, after instantiating the chart area, setting the below code will give you a bigger pie chart. c.Position.Width = 100; c.Position.Height = 100; The width and height values are in percentage. In this case the chart will be generated by utilizing all the width and height of the chart object. See the output updated with the width and height set to 100% each. Generate Chart for sales type share Now for generating the chart according to the sales type, you just need to change the SQL query and x and y values of the chart. The Sql query used is “SELECT SUM(saleAmount) amount, SaleType from SalesData group by SaleType” and the X-Value is amount and Y-Values is SaleType. s.XValueMember = "SaleType"; s.YValueMembers = "amount"; After modifying the above code with these, the following output is generated. Generate Chart for sales progress over time period For generating the progress of sale chart against sales amount / period, line chart is the ideal tool. In order to facilitate the line chart, you can use Chart Type as System.Web.UI.DataVisualization.Charting.SeriesChartType.Line. Also we need to retrieve the amount and sales date from the data source. I have used the following query to facilitate this. “SELECT SaleAmount, SaleDate FROM SalesData” The output for the line chart is as follows Now you have seen how easily you can build various types of charts. Chart control is an excellent one that helps you to bring business intelligence to your applications. What I demonstrated in only a small part of what you can do with the chart control. Refer http://msdn.microsoft.com/en-us/library/dd456632.aspx for further reading. If you want to get the project files in zip format, post your email below. Hope you enjoyed reading this article.

    Read the article

  • LINQ und ArcObjects

    - by Marko Apfel
    LINQ und ArcObjects Motivation LINQ1 (language integrated query) ist eine Komponente des Microsoft .NET Frameworks seit der Version 3.5. Es erlaubt eine SQL-ähnliche Abfrage zu verschiedenen Datenquellen wie SQL, XML u.v.m. Wie SQL auch, bietet LINQ dazu eine deklarative Notation der Problemlösung - d.h. man muss nicht im Detail beschreiben wie eine Aufgabe, sondern was überhaupt zu lösen ist. Das befreit den Entwickler abfrageseitig von fehleranfälligen Iterator-Konstrukten. Ideal wäre es natürlich auf diese Möglichkeiten auch in der ArcObjects-Programmierung mit Features zugreifen zu können. Denkbar wäre dann folgendes Konstrukt: var largeFeatures = from feature in features where (feature.GetValue("SHAPE_Area").ToDouble() > 3000) select feature; bzw. dessen Äquivalent als Lambda-Expression: var largeFeatures = features.Where(feature => (feature.GetValue("SHAPE_Area").ToDouble() > 3000)); Dazu muss ein entsprechender Provider zu Verfügung stehen, der die entsprechende Iterator-Logik managt. Dies ist leichter als man auf den ersten Blick denkt - man muss nur die gewünschten Entitäten als IEnumerable<IFeature> liefern. (Anm.: nicht wundern - die Methoden GetValue() und ToDouble() habe ich nebenbei als Erweiterungsmethoden deklariert.) Im Hintergrund baut LINQ selbständig eine Zustandsmaschine (state machine)2 auf deren Ausführung verzögert ist (deferred execution)3 - d.h. dass erst beim tatsächlichen Anfordern von Entitäten (foreach, Count(), ToList(), ..) eine Instanziierung und Verarbeitung stattfindet, obwohl die Zuweisung schon an ganz anderer Stelle erfolgte. Insbesondere bei mehrfacher Iteration durch die Entitäten reibt man sich bei den ersten Debuggings verwundert die Augen wenn der Ausführungszeiger wie von Geisterhand wieder in die Iterator-Logik springt. Realisierung Eine ganz knappe Logik zum Konstruieren von IEnumerable<IFeature> lässt sich mittels Durchlaufen eines IFeatureCursor realisieren. Dazu werden die einzelnen Feature mit yield ausgegeben. Der einfachen Verwendung wegen, habe ich die Logik in eine Erweiterungsmethode GetFeatures() für IFeatureClass aufgenommen: public static IEnumerable GetFeatures(this IFeatureClass featureClass, IQueryFilter queryFilter, RecyclingPolicy policy) { IFeatureCursor featureCursor = featureClass.Search(queryFilter, RecyclingPolicy.Recycle == policy); IFeature feature; while (null != (feature = featureCursor.NextFeature())) { yield return feature; } //this is skipped in unit tests with cursor-mock if (Marshal.IsComObject(featureCursor)) { Marshal.ReleaseComObject(featureCursor); } } Damit kann man sich nun ganz einfach die IEnumerable<IFeature> erzeugen lassen: IEnumerable features = _featureClass.GetFeatures(RecyclingPolicy.DoNotRecycle); Etwas aufpassen muss man bei der Verwendung des "Recycling-Cursors". Nach einer verzögerten Ausführung darf im selben Kontext nicht erneut über die Features iteriert werden. In diesem Fall wird nämlich nur noch der Inhalt des letzten (recycelten) Features geliefert und alle Features sind innerhalb der Menge gleich. Kritisch würde daher das Konstrukt largeFeatures.ToList(). ForEach(feature => Debug.WriteLine(feature.OID)); weil ToList() schon einmal durch die Liste iteriert und der Cursor somit einmal durch die Features bewegt wurde. Die Erweiterungsmethode ForEach liefert dann immer dasselbe Feature. In derartigen Situationen darf also kein Cursor mit Recycling verwendet werden. Ein mehrfaches Ausführen von foreach ist hingegen kein Problem weil dafür jedes Mal die Zustandsmaschine neu instanziiert wird und somit der Cursor neu durchlaufen wird – das ist die oben schon erwähnte Magie. Ausblick Nun kann man auch einen Schritt weiter gehen und ganz eigene Implementierungen für die Schnittstelle IEnumerable<IFeature> in Angriff nehmen. Dazu müssen nur die Methode und das Property zum Zugriff auf den Enumerator ausprogrammiert werden. Im Enumerator selbst veranlasst man in der Reset()-Methode das erneute Ausführen der Suche – dazu übergibt man beispielsweise ein entsprechendes Delegate in den Konstruktur: new FeatureEnumerator( _featureClass, featureClass => featureClass.Search(_filter, isRecyclingCursor)); und ruft dieses beim Reset auf: public void Reset() {     _featureCursor = _resetCursor(_t); } Auf diese Art und Weise können Enumeratoren für völlig verschiedene Szenarien implementiert werden, die clientseitig restlos identisch nach obigen Schema verwendet werden. Damit verschmelzen Cursors, SelectionSets u.s.w. zu einer einzigen Materie und die Wiederverwendbarkeit von Code steigt immens. Obendrein lässt sich ein IEnumerable in automatisierten Unit-Tests sehr einfach mocken - ein großer Schritt in Richtung höherer Software-Qualität.4 Fazit Nichtsdestotrotz ist Vorsicht mit diesen Konstrukten in performance-relevante Abfragen geboten. Dadurch dass im Hintergrund eine Zustandsmaschine verwalten wird, entsteht einiges an Overhead dessen Verarbeitung zusätzliche Zeit kostet - ca. 20 bis 100 Prozent. Darüber hinaus ist auch das Arbeiten ohne Recycling schnell ein Performance-Gap. Allerdings ist deklarativer LINQ-Code viel eleganter, fehlerfreier und wartungsfreundlicher als das manuelle Iterieren, Vergleichen und Aufbauen einer Ergebnisliste. Der Code-Umfang verringert sich erfahrungsgemäß im Schnitt um 75 bis 90 Prozent! Dafür warte ich gerne ein paar Millisekunden länger. Wie so oft muss abgewogen werden zwischen Wartbarkeit und Performance - wobei für mich Wartbarkeit zunehmend an Priorität gewinnt. Zumeist ist sowieso nicht der Code sondern der Anwender die Bremse im Prozess. Demo-Quellcode support.esri.de   [1] Wikipedia: LINQ http://de.wikipedia.org/wiki/LINQ [2] Wikipedia: Zustandsmaschine http://de.wikipedia.org/wiki/Endlicher_Automat [3] Charlie Calverts Blog: LINQ and Deferred Execution http://blogs.msdn.com/b/charlie/archive/2007/12/09/deferred-execution.aspx [4] Clean Code Developer - gelber Grad/Automatisierte Unit Tests http://www.clean-code-developer.de/Gelber-Grad.ashx#Automatisierte_Unit_Tests_8

    Read the article

  • Tuning Red Gate: #2 of Many

    - by Grant Fritchey
    In the last installment, I used the SQL Monitor tool to get a snapshot view of the current state of the servers at Red Gate that are giving us trouble. That snapshot suggested some areas where I should focus some time, primarily in which queries were being called most frequently or were running the longest. But, you don't want to just run off & start tuning queries. Remember, the foundation for query tuning is the server itself. So, I want to be sure I'm not looking at some major hardware or configuration issues that I need to address first. Rather than look at the current status of the server, I'm going to look at historical data. Clicking on the Analysis tab of SQL Monitor I get a whole list of counters that I can look at. More importantly, I can look at them over a period of time. Even more importantly, I can compare past periods with current periods to see if we're looking at a progressive issue or not. There are counters here that will give me an indication of load, and there are counters here that will tell me specifics about that load. First, I want to just look at the load to understand where the pain points might be. Trying to drill down before you have detailed information is just bad planning. First thing I'm going to check is the CPU, just to see what's up there. I have two servers I'm interested in, so I'll show you both: Looking at the last 30 days for both servers, well, let's just say that the first server is about what I would expect. It has an average baseline behavior with occasional, regular, peaks. This looks like a system with a fairly steady & predictable load that probably has a nightly batch process that spikes the processor. In short, normal stuff. The points there where the CPU drops radically. that might be worth investigating further because something changed the processing on this system a lot. But the first server. It's all over the place. There's no steady CPU behavior at all. It's spike high for long periods of time. It's up, it's down. I'm really going to have to spend time looking at CPU issues on this server to try to figure out what's up. It might be other processes being shared on the server, it might be something else. Either way, I'm going to have to spend time evaluating this CPU, especially those peeks about a week ago. Looking at the Pages/sec, again, just a measure of load, I see that there are some peaks on the rg-sql02 server, but over all, it looks like a fairly standard load. Plus, the peaks are only up to 550 pages/sec. Remember, this isn't a performance measure, but just a load measurement, but from this, I don't think we're looking at major memory issues, but I may want to correlate these counters with the CPU counters. Again, the other server looks like there's stuff going on. The load is not at all consistent. In fact there was a point earlier in the year that looks pretty severe. Plus the spikes here are twice the size of the other system. We've got a lot more load going on here and I will probably need to drill down on memory usage on this server. Taking a look at the disk transfers/sec the load on both systems seems to roughly correspond to the other load indicators. Notice that drop right in the middle of the graph for rg-sql02. I wonder if the office was closed over that period or a system was down for maintenance. If I saw spikes in memory or disk that corresponded to the drip in CPU, you can assume something was using those other resources and causing a drop, but when everything goes down, it just means that the system isn't gettting used. The disk on the rg-sql01 system isn't spiking exactly the same way as the memory & cpu, so there's a good chance (chance mind you) that any performance issues might not be disk related. However, notice that huge jump at the beginning of the month. Several disks were used more than they were for the rest of the month. That's the load on the server. What about the load on SQL Server itself? Next time.

    Read the article

  • Interview with Ronald Bradford about MySQL Connect

    - by Keith Larson
    Ronald Bradford,  an Oracle ACE Director has been busy working with  database consulting, book writing (EffectiveMySQL) while traveling and speaking around the world in support of MySQL. I was able to take some of his time to get an interview on this thoughts about theMySQL Connect conference. Keith Larson: What where your thoughts when you heard that Oracle was going to provide the community the MySQL Conference ?Ronald Bradford: Oracle has already been providing various different local community events including OTN Tech Days and  MySQL community days. These are great for local regions both in the US and abroad.  In previous years there has been an increase of content at Oracle Open World, however that benefits the Oracle community far more then the MySQL community.  It is good to see that Oracle is realizing the benefit in providing a large scale dedicated event for the MySQL community that includes speakers from the MySQL development teams, invested companies in the ecosystem and other community evangelists.I fully expect a successful event and look forward to hopefully seeing MySQL Connect at the upcoming Brazil and Japan OOW conferences and perhaps an event on the East Coast.Keith Larson: Since you are part of the content committee, what did you think of the submissions that were received during call for papers?Ronald Bradford: There was a large number of quality submissions to the number of available presentation sessions. As with the previous years as a committee member for the annual MySQL conference, there is always a large variety of common cornerstone MySQL features as well as new products and upcoming companies sharing their MySQL experiences. All of the usual major players in the ecosystem will in presenting at MySQL Connect including Facebook, Twitter, Yahoo, Continuent, Percona, Tokutek, Sphinx and Amazon to name a few.  This is ensuring the event will have a large number of quality speakers and a difficult time in choosing what to attend. Keith Larson: What sessions do you look forwarding to attending? Ronald Bradford: As with most quality conferences you can only be in one place at one time, so with multiple tracks per session it is always difficult to decide. The continued work and success with MySQL Cluster, and with a number of sessions I am sure will be popular. The features that interest me the most are around the optimizer, where there are several sessions on new features, and on the importance of backups. There are three presentations in this area to choose from.Keith Larson: Are you going to cover any of the content in your books at your MySQL Connect sessions?Ronald Bradford: I will be giving two presentations at MySQL Connect. The first will include the techniques available for creating better indexes where I will be touching on some aspects of the first Effective MySQL book on Optimizing SQL Statements.  In my second presentation from experiences of managing 500+ AWS MySQL instances, I will be touching on areas including SQL tuning, backup and recovery and scale out with replication.   These are the key topics of the initial books in the Effective MySQL series that focus on performance, scalability and business continuity.  The books however cover a far greater amount of detail then can be presented in a 1 hour session. Keith Larson: What features of MySQL 5.6 do you look forward to the most ?Ronald Bradford: I am very impressed with the optimizer trace feature. The ability to see exposed information is invaluable not just for MySQL 5.6, but to also apply information discerned for optimizing SQL statements in earlier versions of MySQL.  Not everybody understands that it is easy to deploy a MySQL 5.6 slave into an existing topology running an older version if MySQL for evaluation of many new features.  You can use the new mysqlbinlog streaming feature for duplicating master binary logs on an older version with a MySQL 5.6 slave.  The improvements in instrumentation in the Performance Schema are exciting.   However, as with my upcoming Replication Techniques in Depth title, that will be available for sale at MySQL Connect, there are numerous replication features, some long overdue with provide significant management benefits. Crash Save Slaves, Global transaction Identifiers (GTID)  and checksums just to mention a few.Keith Larson: You have been to numerous conferences, what would you recommend for people at the conference? Ronald Bradford: Make the time to meet and introduce yourself to the speakers that cover the topics that most interest you. The MySQL ecosystem has a very strong community.  The relationships you build with presenters, developers and architects in MySQL can be invaluable, however they are created over time. Get to know these people, interact with them over time.  This is the opportunity to learn more then just the content from a 1 hour session. Keith Larson: Any additional tips to handling the long hours ? Ronald Bradford: Conferences can be hard, especially with all the post event drinking.  This is a two day event and I am sure will include additional events on Friday and Saturday night so come well prepared, and leave work behind. Take the time to learn something new.   You can always catchup on sleep later. Keith Larson: Thank you so much for taking some time to do this I look forward to seeing you at the MySQL Connect conference.  Please stay tuned here for more updates on MySQL. 

    Read the article

  • JDK bug migration: components and subcomponents

    - by darcy
    One subtask of the JDK migration from the legacy bug tracking system to JIRA was reclassifying bugs from a three-level taxonomy in the legacy system, (product, category, subcategory), to a fundamentally two-level scheme in our customized JIRA instance, (component, subcomponent). In the JDK JIRA system, there is technically a third project-level classification, but by design a large majority of JDK-related bugs were migrated into a single "JDK" project. In the end, over 450 legacy subcategories were simplified into about 120 subcomponents in JIRA. The 120 subcomponents are distributed among 17 components. A rule of thumb used was that a subcategory had to have at least 50 bugs in it for it to be retained. Below is a listing the component / subcomponent classification of the JDK JIRA project along with some notes and guidance on which OpenJDK email addresses cover different areas. Eventually, a separate incidents project to host new issues filed at bugs.sun.com will use a slightly simplified version of this scheme. The preponderance of bugs and subcomponents for the JDK are in library-related areas, with components named foo-libs and subcomponents primarily named after packages. While there was an overall condensation of subcomponents in the migration, in some cases long-standing informal divisions in core libraries based on naming conventions in the description were promoted to formal subcomponents. For example, hundreds of bugs in the java.util subcomponent whose descriptions started with "(coll)" were moved into java.util:collections. Likewise, java.lang bugs starting with "(reflect)" and "(proxy)" were moved into java.lang:reflect. client-libs (Predominantly discussed on 2d-dev and awt-dev and swing-dev.) 2d demo java.awt java.awt:i18n java.beans (See beans-dev.) javax.accessibility javax.imageio javax.sound (See sound-dev.) javax.swing core-libs (See core-libs-dev.) java.io java.io:serialization java.lang java.lang.invoke java.lang:class_loading java.lang:reflect java.math java.net java.nio (Discussed on nio-dev.) java.nio.charsets java.rmi java.sql java.sql:bridge java.text java.util java.util.concurrent java.util.jar java.util.logging java.util.regex java.util:collections java.util:i18n javax.annotation.processing javax.lang.model javax.naming (JNDI) javax.script javax.script:javascript javax.sql org.openjdk.jigsaw (See jigsaw-dev.) security-libs (See security-dev.) java.security javax.crypto (JCE: includes SunJCE/MSCAPI/UCRYPTO/ECC) javax.crypto:pkcs11 (JCE: PKCS11 only) javax.net.ssl (JSSE, includes javax.security.cert) javax.security javax.smartcardio javax.xml.crypto org.ietf.jgss org.ietf.jgss:krb5 other-libs corba corba:idl corba:orb corba:rmi-iiop javadb other (When no other subcomponent is more appropriate; use judiciously.) Most of the subcomponents in the xml component are related to jaxp. xml jax-ws jaxb javax.xml.parsers (JAXP) javax.xml.stream (JAXP) javax.xml.transform (JAXP) javax.xml.validation (JAXP) javax.xml.xpath (JAXP) jaxp (JAXP) org.w3c.dom (JAXP) org.xml.sax (JAXP) For OpenJDK, most JVM-related bugs are connected to the HotSpot Java virtual machine. hotspot (See hotspot-dev.) build compiler (See hotspot-compiler-dev.) gc (garbage collection, see hotspot-gc-dev.) jfr (Java Flight Recorder) jni (Java Native Interface) jvmti (JVM Tool Interface) mvm (Multi-Tasking Virtual Machine) runtime (See hotspot-runtime-dev.) svc (Servicability) test core-svc (See serviceability-dev.) debugger java.lang.instrument java.lang.management javax.management tools The full JDK bug database contains entries related to legacy virtual machines that predate HotSpot as well as retired APIs. vm-legacy jit (Sun Exact VM) jit_symantec (Symantec VM, before Exact VM) jvmdi (JVM Debug Interface ) jvmpi (JVM Profiler Interface ) runtime (Exact VM Runtime) Notable command line tools in the $JDK/bin directory have corresponding subcomponents. tools appletviewer apt (See compiler-dev.) hprof jar javac (See compiler-dev.) javadoc(tool) (See compiler-dev.) javah (See compiler-dev.) javap (See compiler-dev.) jconsole launcher updaters (Timezone updaters, etc.) visualvm Some aspects of JDK infrastructure directly affect JDK Hg repositories, but other do not. infrastructure build (See build-dev and build-infra-dev.) licensing (Covers updates to the third party readme, licenses, and similar files.) release_eng (Release engineering) staging (Staging of web pages related to JDK releases.) The specification subcomponent encompasses the formal language and virtual machine specifications. specification language (The Java Language Specification) vm (The Java Virtual Machine Specification) The code for the deploy and install areas is not currently included in OpenJDK. deploy deployment_toolkit plugin webstart install auto_update install servicetags In the JDK, there are a number of cross-cutting concerns whose organization is essentially orthogonal to other areas. Since these areas generally have dedicated teams working on them, it is easier to find bugs of interest if these bugs are grouped first by their cross-cutting component rather than by the affected technology. docs doclet guides hotspot release_notes tools tutorial embedded build hotspot libraries globalization locale-data translation performance hotspot libraries The list of subcomponents will no doubt grow over time, but my inclination is to resist that growth since the addition of each subcomponent makes the system as a whole more complicated and harder to use. When the system gets closer to being externalized, I plan to post more blog entries describing recommended use of various custom fields in the JDK project.

    Read the article

  • First Foray&ndash;About timeout

    - by SQLMonger
    It has been quite a while since I signed up for this blog site and high time that something was posted.  I have a list of topics that I will be working through and posting.  Some I am sure will have been posted by others, but I will be sticking to the technical problems and challenges that I’ve recently faced, and the solutions that worked for me.  My motto when learning something new has always been “My kingdom for an example!”, and I plan on delivering useful examples here so others can learn from my efforts, failures and successes.   A bit of background about me… My name is Clayton Groom. I am a founding partner of a consulting firm in St. Louis Missouri, Covenant Technology Partners, LLC and focus on SQL Server Data Warehouse design, Analysis Services and Enterprise Reporting solutions.  I have been working with SQL Server since the early nineties, when it still only ran on OS/2. I love solving puzzles and technical challenges.   Enough about me… On to a real problem… SSIS Connection Time outs versus Command Time outs Last week, I was working on automating the processing for a large Analysis Services cube.  I had reworked an SSIS package and script task originally posted by Vidas Matelis that automates the process of adding new and dropping old partitions to/from an Analysis Services cube.  I had the package working great, tested, and ready for deployment.  It basically performs a query against the source system to determine if there is new data in the warehouse that will require a new partition to be added to the cube, and it checks the cube to see if there are any partitions that are present that are no longer needed in a rolling 60 month window. My client uses Tivoli for running all their production jobs, and not SQL Agent, so I had to build a command line file for Tivoli to use to run the package. Everything was going great. I had tested the command file from my development workstation using an XML configuration file to pass in server-specific parameters into the package when executed using the DTExec utility. With all the pieces ready, I updated the dtsconfig file to point to the UAT environment and started working with the Tivoli developer to test the job.  On the first run, the job failed, and from what I could see in the SSIS log, it had failed because of a timeout. Other errors in the log made me think that perhaps the connection string had not been passed into the package correctly. We bumped the Connection Manager  timeout values from 20 seconds to 120 seconds and tried again. The job still failed. After changing the command line to use the /SET option instead of the /CONFIGFILE option, we tested again, and again failure. After a number more failed attempts, and getting the Teradata DBA involved to monitor and see if we were connecting and failing or just failing to connect, we determined that the job was indeed connecting to the server and then disconnecting itself after 30 seconds.  This seemed odd, as we had the timeout values for the connection manager set to 180 seconds by then.  At this point one of the DBA’s found a post on the Teradata forum that had the clues to the puzzle: There is a separate “CommandTimeout” custom property on the Data source object that may needed to be adjusted for longer running queries.  I opened up the SSIS package, opened the data flow task that generated the partition list table and right-clicked on the data source. from the context menu, I selected “Show Advanced Editor” and found the property. Sure enough, it was set to 30 seconds. The CommandTimeout property can also be edited in the SSIS Properties sheet. In order to determine how long the timeout needed to be, I ran the query from the task in the development environment and received a response in a matter of seconds.  I then tried the same query against the production database and waited several minutes for a response. This did not seem to be a reasonable response time for the query involved, and indeed it wasn’t. The Teradata DBA’s adjusted the query governor settings for the service account I was testing with, and we were able to get the response back down under a minute.  Still, I set the CommandTimeout property to a much higher value in case the job was ever started during a time of high-demand on the production server. With this change in place, the job finally completed successfully.  The lesson learned for me was two-fold: Always compare query execution times between development and production environments, and don’t assume that production will always be faster.  With higher user demands, query governors, and a whole lot more data, the execution time of even what might seem to be simple queries can vary greatly. SSIS Connection time out settings do not affect command time outs.  Connection timeouts control how long the package will wait for a response from the server before assuming the server is not available or is not responding. Command time outs control how long a task will wait for results to start being returned before deciding that the server is not responding. Both lessons seem pretty straight forward, and I felt pretty sheepish once I finally figured out what the issue was.  To be fair though, In the 5+ years that I have been working with SSIS, I could only recall one other time where I had to set the CommandTimeout property, and that memory only resurfaced while I was penning this post.

    Read the article

  • ROracle support for TimesTen In-Memory Database

    - by Sam Drake
    Today's guest post comes from Jason Feldhaus, a Consulting Member of Technical Staff in the TimesTen Database organization at Oracle.  He shares with us a sample session using ROracle with the TimesTen In-Memory database.  Beginning in version 1.1-4, ROracle includes support for the Oracle Times Ten In-Memory Database, version 11.2.2. TimesTen is a relational database providing very fast and high throughput through its memory-centric architecture.  TimesTen is designed for low latency, high-volume data, and event and transaction management. A TimesTen database resides entirely in memory, so no disk I/O is required for transactions and query operations. TimesTen is used in applications requiring very fast and predictable response time, such as real-time financial services trading applications and large web applications. TimesTen can be used as the database of record or as a relational cache database to Oracle Database. ROracle provides an interface between R and the database, providing the rich functionality of the R statistical programming environment using the SQL query language. ROracle uses the OCI libraries to handle database connections, providing much better performance than standard ODBC.The latest ROracle enhancements include: Support for Oracle TimesTen In-Memory Database Support for Date-Time using R's POSIXct/POSIXlt data types RAW, BLOB and BFILE data type support Option to specify number of rows per fetch operation Option to prefetch LOB data Break support using Ctrl-C Statement caching support Times Ten 11.2.2 contains enhanced support for analytics workloads and complex queries: Analytic functions: AVG, SUM, COUNT, MAX, MIN, DENSE_RANK, RANK, ROW_NUMBER, FIRST_VALUE and LAST_VALUE Analytic clauses: OVER PARTITION BY and OVER ORDER BY Multidimensional grouping operators: Grouping clauses: GROUP BY CUBE, GROUP BY ROLLUP, GROUP BY GROUPING SETS Grouping functions: GROUP, GROUPING_ID, GROUP_ID WITH clause, which allows repeated references to a named subquery block Aggregate expressions over DISTINCT expressions General expressions that return a character string in the source or a pattern within the LIKE predicate Ability to order nulls first or last in a sort result (NULLS FIRST or NULLS LAST in the ORDER BY clause) Note: Some functionality is only available with Oracle Exalytics, refer to the TimesTen product licensing document for details. Connecting to TimesTen is easy with ROracle. Simply install and load the ROracle package and load the driver. > install.packages("ROracle") > library(ROracle) Loading required package: DBI > drv <- dbDriver("Oracle") Once the ROracle package is installed, create a database connection object and connect to a TimesTen direct driver DSN as the OS user. > conn <- dbConnect(drv, username ="", password="", dbname = "localhost/SampleDb_1122:timesten_direct") You have the option to report the server type - Oracle or TimesTen? > print (paste ("Server type =", dbGetInfo (conn)$serverType)) [1] "Server type = TimesTen IMDB" To create tables in the database using R data frame objects, use the function dbWriteTable. In the following example we write the built-in iris data frame to TimesTen. The iris data set is a small example data set containing 150 rows and 5 columns. We include it here not to highlight performance, but so users can easily run this example in their R session. > dbWriteTable (conn, "IRIS", iris, overwrite=TRUE, ora.number=FALSE) [1] TRUE Verify that the newly created IRIS table is available in the database. To list the available tables and table columns in the database, use dbListTables and dbListFields, respectively. > dbListTables (conn) [1] "IRIS" > dbListFields (conn, "IRIS") [1] "SEPAL.LENGTH" "SEPAL.WIDTH" "PETAL.LENGTH" "PETAL.WIDTH" "SPECIES" To retrieve a summary of the data from the database we need to save the results to a local object. The following call saves the results of the query as a local R object, iris.summary. The ROracle function dbGetQuery is used to execute an arbitrary SQL statement against the database. When connected to TimesTen, the SQL statement is processed completely within main memory for the fastest response time. > iris.summary <- dbGetQuery(conn, 'SELECT SPECIES, AVG ("SEPAL.LENGTH") AS AVG_SLENGTH, AVG ("SEPAL.WIDTH") AS AVG_SWIDTH, AVG ("PETAL.LENGTH") AS AVG_PLENGTH, AVG ("PETAL.WIDTH") AS AVG_PWIDTH FROM IRIS GROUP BY ROLLUP (SPECIES)') > iris.summary SPECIES AVG_SLENGTH AVG_SWIDTH AVG_PLENGTH AVG_PWIDTH 1 setosa 5.006000 3.428000 1.462 0.246000 2 versicolor 5.936000 2.770000 4.260 1.326000 3 virginica 6.588000 2.974000 5.552 2.026000 4 <NA> 5.843333 3.057333 3.758 1.199333 Finally, disconnect from the TimesTen Database. > dbCommit (conn) [1] TRUE > dbDisconnect (conn) [1] TRUE We encourage you download Oracle software for evaluation from the Oracle Technology Network. See these links for our software: Times Ten In-Memory Database,  ROracle.  As always, we welcome comments and questions on the TimesTen and  Oracle R technical forums.

    Read the article

  • Database Owner Conundrum

    - by Johnm
    Have you ever restored a database from a production environment on Server A into a development environment on Server B and had some items, such as Service Broker, mysteriously cease functioning? You might want to consider reviewing the database owner property of the database. The Scenario Recently, I was developing some messaging functionality that utilized the Service Broker feature of SQL Server in a development environment. Within the instance of the development environment resided two databases: One was a restored version of a production database that we will call "RestoreDB". The second database was a brand new database that has yet to exist in the production environment that we will call "DevDB". The goal is to setup a communication path between RestoreDB and DevDB that will later be implemented into the production database. After implementing all of the Service Broker objects that are required to communicate within a database as well as between two databases on the same instance I found myself a bit confounded. My testing was showing that the communication was successful when it was occurring internally within DevDB; but the communication between RestoreDB and DevDB did not appear to be working. Profiler to the rescue After carefully reviewing my code for any misspellings, missing commas or any other minor items that might be a syntactical cause of failure, I decided to launch Profiler to aid in the troubleshooting. After simulating the cross database messaging, I noticed the following error appearing in Profiler: An exception occurred while enqueueing a message in the target queue. Error: 33009, State: 2. The database owner SID recorded in the master database differs from the database owner SID recorded in database '[Database Name Here]'. You should correct this situation by resetting the owner of database '[Database Name Here]' using the ALTER AUTHORIZATION statement. Now, this error message is a helpful one. Not only does it identify the issue in plain language, it also provides a potential solution. An execution of the following query that utilizes the catalog view sys.transmission_queue revealed the same error message for each communication attempt: SELECT     * FROM        sys.transmission_queue; Seeing the situation as a learning opportunity I dove a bit deeper. Reviewing the database properties  The owner of a specific database can be easily viewed by right-clicking the database in SQL Server Management Studio and selecting the "properties" option. The owner is listed on the "General" page of the properties screen. In my scenario, the database in the production server was created by Frank the DBA; therefore his server login appeared as the owner: "ServerName\Frank". While this is interesting information, it certainly doesn't tell me much in regard to the SID (security identifier) and its existence, or lack thereof, in the master database as the error suggested. I pulled together the following query to gather more interesting information: SELECT     a.name     , a.owner_sid     , b.sid     , b.name     , b.type_desc FROM        master.sys.databases a     LEFT OUTER JOIN master.sys.server_principals b         ON a.owner_sid = b.sid WHERE     a.name not in ('master','tempdb','model','msdb'); This query also helped identify how many other user databases in the instance were experiencing the same issue. In this scenario, I saw that there were no matching SIDs in server_principals to the owner SID for my database. What login should be used as the database owner instead of Frank's? The system stored procedure sp_helplogins will provide a list of the valid logins that can be used. Here is an example of its use, revealing all available logins: EXEC sp_helplogins;  Fixing a hole The error message stated that the recommended solution was to execute the ALTER AUTHORIZATION statement. The full statement for this scenario would appear as follows: ALTER AUTHORIZATION ON DATABASE:: [Database Name Here] TO [Login Name]; Another option is to execute the following statement using the sp_changedbowner system stored procedure; but please keep in mind that this stored procedure has been deprecated and will likely disappear in future versions of SQL Server: EXEC dbo.sp_changedbowner @loginname = [Login Name]; .And They Lived Happily Ever After Upon changing the database owner to an existing login and simulating the inner and cross database messaging the errors have ceased. More importantly, all messages sent through this feature now successfully complete their journey. I have added the ownership change to my restoration script for the development environment.

    Read the article

  • ROracle support for TimesTen In-Memory Database

    - by Sherry LaMonica
    Today's guest post comes from Jason Feldhaus, a Consulting Member of Technical Staff in the TimesTen Database organization at Oracle.  He shares with us a sample session using ROracle with the TimesTen In-Memory database.  Beginning in version 1.1-4, ROracle includes support for the Oracle Times Ten In-Memory Database, version 11.2.2. TimesTen is a relational database providing very fast and high throughput through its memory-centric architecture.  TimesTen is designed for low latency, high-volume data, and event and transaction management. A TimesTen database resides entirely in memory, so no disk I/O is required for transactions and query operations. TimesTen is used in applications requiring very fast and predictable response time, such as real-time financial services trading applications and large web applications. TimesTen can be used as the database of record or as a relational cache database to Oracle Database. ROracle provides an interface between R and the database, providing the rich functionality of the R statistical programming environment using the SQL query language. ROracle uses the OCI libraries to handle database connections, providing much better performance than standard ODBC.The latest ROracle enhancements include: Support for Oracle TimesTen In-Memory Database Support for Date-Time using R's POSIXct/POSIXlt data types RAW, BLOB and BFILE data type support Option to specify number of rows per fetch operation Option to prefetch LOB data Break support using Ctrl-C Statement caching support Times Ten 11.2.2 contains enhanced support for analytics workloads and complex queries: Analytic functions: AVG, SUM, COUNT, MAX, MIN, DENSE_RANK, RANK, ROW_NUMBER, FIRST_VALUE and LAST_VALUE Analytic clauses: OVER PARTITION BY and OVER ORDER BY Multidimensional grouping operators: Grouping clauses: GROUP BY CUBE, GROUP BY ROLLUP, GROUP BY GROUPING SETS Grouping functions: GROUP, GROUPING_ID, GROUP_ID WITH clause, which allows repeated references to a named subquery block Aggregate expressions over DISTINCT expressions General expressions that return a character string in the source or a pattern within the LIKE predicate Ability to order nulls first or last in a sort result (NULLS FIRST or NULLS LAST in the ORDER BY clause) Note: Some functionality is only available with Oracle Exalytics, refer to the TimesTen product licensing document for details. Connecting to TimesTen is easy with ROracle. Simply install and load the ROracle package and load the driver. > install.packages("ROracle") > library(ROracle) Loading required package: DBI > drv <- dbDriver("Oracle") Once the ROracle package is installed, create a database connection object and connect to a TimesTen direct driver DSN as the OS user. > conn <- dbConnect(drv, username ="", password="", dbname = "localhost/SampleDb_1122:timesten_direct") You have the option to report the server type - Oracle or TimesTen? > print (paste ("Server type =", dbGetInfo (conn)$serverType)) [1] "Server type = TimesTen IMDB" To create tables in the database using R data frame objects, use the function dbWriteTable. In the following example we write the built-in iris data frame to TimesTen. The iris data set is a small example data set containing 150 rows and 5 columns. We include it here not to highlight performance, but so users can easily run this example in their R session. > dbWriteTable (conn, "IRIS", iris, overwrite=TRUE, ora.number=FALSE) [1] TRUE Verify that the newly created IRIS table is available in the database. To list the available tables and table columns in the database, use dbListTables and dbListFields, respectively. > dbListTables (conn) [1] "IRIS" > dbListFields (conn, "IRIS") [1] "SEPAL.LENGTH" "SEPAL.WIDTH" "PETAL.LENGTH" "PETAL.WIDTH" "SPECIES" To retrieve a summary of the data from the database we need to save the results to a local object. The following call saves the results of the query as a local R object, iris.summary. The ROracle function dbGetQuery is used to execute an arbitrary SQL statement against the database. When connected to TimesTen, the SQL statement is processed completely within main memory for the fastest response time. > iris.summary <- dbGetQuery(conn, 'SELECT SPECIES, AVG ("SEPAL.LENGTH") AS AVG_SLENGTH, AVG ("SEPAL.WIDTH") AS AVG_SWIDTH, AVG ("PETAL.LENGTH") AS AVG_PLENGTH, AVG ("PETAL.WIDTH") AS AVG_PWIDTH FROM IRIS GROUP BY ROLLUP (SPECIES)') > iris.summary SPECIES AVG_SLENGTH AVG_SWIDTH AVG_PLENGTH AVG_PWIDTH 1 setosa 5.006000 3.428000 1.462 0.246000 2 versicolor 5.936000 2.770000 4.260 1.326000 3 virginica 6.588000 2.974000 5.552 2.026000 4 <NA> 5.843333 3.057333 3.758 1.199333 Finally, disconnect from the TimesTen Database. > dbCommit (conn) [1] TRUE > dbDisconnect (conn) [1] TRUE We encourage you download Oracle software for evaluation from the Oracle Technology Network. See these links for our software: Times Ten In-Memory Database,  ROracle.  As always, we welcome comments and questions on the TimesTen and  Oracle R technical forums.

    Read the article

  • ADF Business Components

    - by Arda Eralp
    ADF Business Components and JDeveloper simplify the development, delivery, and customization of business applications for the Java EE platform. With ADF Business Components, developers aren't required to write the application infrastructure code required by the typical Java EE application to: Connect to the database Retrieve data Lock database records Manage transactions   ADF Business Components addresses these tasks through its library of reusable software components and through the supporting design time facilities in JDeveloper. Most importantly, developers save time using ADF Business Components since the JDeveloper design time makes typical development tasks entirely declarative. In particular, JDeveloper supports declarative development with ADF Business Components to: Author and test business logic in components which automatically integrate with databases Reuse business logic through multiple SQL-based views of data, supporting different application tasks Access and update the views from browser, desktop, mobile, and web service clients Customize application functionality in layers without requiring modification of the delivered application The goal of ADF Business Components is to make the business services developer more productive.   ADF Business Components provides a foundation of Java classes that allow your business-tier application components to leverage the functionality provided in the following areas: Simplifying Data Access Design a data model for client displays, including only necessary data Include master-detail hierarchies of any complexity as part of the data model Implement end-user Query-by-Example data filtering without code Automatically coordinate data model changes with business services layer Automatically validate and save any changes to the database   Enforcing Business Domain Validation and Business Logic Declaratively enforce required fields, primary key uniqueness, data precision-scale, and foreign key references Easily capture and enforce both simple and complex business rules, programmatically or declaratively, with multilevel validation support Navigate relationships between business domain objects and enforce constraints related to compound components   Supporting Sophisticated UIs with Multipage Units of Work Automatically reflect changes made by business service application logic in the user interface Retrieve reference information from related tables, and automatically maintain the information when the user changes foreign-key values Simplify multistep web-based business transactions with automatic web-tier state management Handle images, video, sound, and documents without having to use code Synchronize pending data changes across multiple views of data Consistently apply prompts, tooltips, format masks, and error messages in any application Define custom metadata for any business components to support metadata-driven user interface or application functionality Add dynamic attributes at runtime to simplify per-row state management   Implementing High-Performance Service-Oriented Architecture Support highly functional web service interfaces for business integration without writing code Enforce best-practice interface-based programming style Simplify application security with automatic JAAS integration and audit maintenance "Write once, run anywhere": use the same business service as plain Java class, EJB session bean, or web service   Streamlining Application Customization Extend component functionality after delivery without modifying source code Globally substitute delivered components with extended ones without modifying the application   ADF Business Components implements the business service through the following set of cooperating components: Entity object An entity object represents a row in a database table and simplifies modifying its data by handling all data manipulation language (DML) operations for you. These are basically your 1 to 1 representation of a database table. Each table in the database will have 1 and only 1 EO. The EO contains the mapping between columns and attributes. EO's also contain the business logic and validation. These are you core data services. They are responsible for updating, inserting and deleting records. The Attributes tab displays the actual mapping between attributes and columns, the mapping has following fields: Name : contains the name of the attribute we expose in our data model. Type : defines the data type of the attribute in our application. Column : specifies the column to which we want to map the attribute with Column Type : contains the type of the column in the database   View object A view object represents a SQL query. You use the full power of the familiar SQL language to join, filter, sort, and aggregate data into exactly the shape required by the end-user task. The attributes in the View Objects are actually coming from the Entity Object. In the end the VO will generate a query but you basically build a VO by selecting which EO need to participate in the VO and which attributes of those EO you want to use. That's why you have the Entity Usage column so you can see the relation between VO and EO. In the query tab you can clearly see the query that will be generated for the VO. At this stage we don't need it and just use it for information purpose. In later stages we might use it. Application module An application module is the controller of your data layer. It is responsible for keeping hold of the transaction. It exposes the data model to the view layer. You expose the VO's through the Application Module. This is the abstraction of your data layer which you want to show to the outside word.It defines an updatable data model and top-level procedures and functions (called service methods) related to a logical unit of work related to an end-user task. While the base components handle all the common cases through built-in behavior, customization is always possible and the default behavior provided by the base components can be easily overridden or augmented. When you create EO's, a foreign key will be translated into an association in our model. It defines the type of relation and who is the master and child as well as how the visibility of the association looks like. A similar concept exists to identify relations between view objects. These are called view links. These are almost identical as association except that a view link is based upon attributes defined in the view object. It can also be based upon an association. Here's a short summary: Entity Objects: representations of tables Association: Relations between EO's. Representations of foreign keys View Objects: Logical model View Links: Relationships between view objects Application Model: interface to your application  

    Read the article

  • Data Source Security Part 1

    - by Steve Felts
    I’ve written a couple of articles on how to store data source security credentials using the Oracle wallet.  I plan to write a few articles on the various types of security available to WebLogic Server (WLS) data sources.  There are more options than you might think! There have been several enhancements in this area in WLS 10.3.6.  There are a couple of more enhancements planned for release WLS 12.1.2 that I will include here for completeness.  This isn’t intended as a teaser.  If you call your Oracle support person, you can get them now as minor patches to WLS 10.3.6.   The current security documentation is scattered in a few places, has a few incorrect statements, and is missing a few topics.  It also seems that the knowledge of how to apply some of these features isn’t written down.  The goal of these articles is to talk about WLS data source security in a unified way and to introduce some approaches to using the available features.  Introduction to WebLogic Data Source Security Options By default, you define a single database user and password for a data source.  You can store it in the data source descriptor or make use of the Oracle wallet.  This is a very simple and efficient approach to security.  All of the connections in the connection pool are owned by this user and there is no special processing when a connection is given out.  That is, it’s a homogeneous connection pool and any request can get any connection from a security perspective (there are other aspects like affinity).  Regardless of the end user of the application, all connections in the pool use the same security credentials to access the DBMS.   No additional information is needed when you get a connection because it’s all available from the data source descriptor (or wallet). java.sql.Connection conn =  mydatasource.getConnection(); Note: You can enter the password as a name-value pair in the Properties field (this not permitted for production environments) or you can enter it in the Password field of the data source descriptor. The value in the Password field overrides any password value defined in the Properties passed to the JDBC Driver when creating physical database connections. It is recommended that you use the Password attribute in place of the password property in the properties string because the Password value is encrypted in the configuration file (stored as the password-encrypted attribute in the jdbc-driver-params tag in the module file) and is hidden in the administration console.  The Properties and Password fields are located on the administration console Data Source creation wizard or Data Source Configuration tab. The JDBC API can also be used to programmatically specify a database user name and password as in the following.  java.sql.Connection conn = mydatasource.getConnection(“user”, “password”); According to the JDBC specification, it’s supposed to take a database user and associated password but different vendors implement this differently.  WLS, by default, treats this as an application server user and password.  The pair is authenticated to see if it’s a valid user and that user is used for WLS security permission checks.  By default, the user is then mapped to a database user and password using the data source credential mapper, so this API sort of follows the specification but database credentials are one-step removed from the application code.  More details and the rationale are described later. While the default approach is simple, it does mean that only one database user is doing all of the work.  You can’t figure out who actually did the update and you can’t restrict SQL operations by who is running the operation, at least at the database level.   Any type of per-user logic will need to be in the application code instead of having the database do it.  There are various WLS data source features that can be configured to provide some per-user information about the operations to the database. WebLogic Data Source Security Options This table describes the features available for WebLogic data sources to configure database security credentials and a brief description.  It also captures information about the compatibility of these features with one another. Feature Description Can be used with Can’t be used with User authentication (default) Default getConnection(user, password) behavior – validate the input and use the user/password in the descriptor. Set client identifier Proxy Session, Identity pooling, Use database credentials Use database credentials Instead of using the credential mapper, use the supplied user and password directly. Set client identifier, Proxy session, Identity pooling User authentication, Multi Data Source Set Client Identifier Set a client identifier property associated with the connection (Oracle and DB2 only). Everything Proxy Session Set a light-weight proxy user associated with the connection (Oracle-only). Set client identifier, Use database credentials Identity pooling, User authentication Identity pooling Heterogeneous pool of connections owned by specified users. Set client identifier, Use database credentials Proxy session, User authentication, Labeling, Multi-datasource, Active GridLink Note that all of these features are available with both XA and non-XA drivers. Currently, the Proxy Session and Use Database Credentials options are on the Oracle tab of the Data Source Configuration tab of the administration console (even though the Use Database Credentials feature is not just for Oracle databases – oops).  The rest of the features are on the Identity tab of the Data Source Configuration tab in the administration console (plan on seeing them all in one place in the future). The subsequent articles will describe these features in more detail.  Keep referring back to this table to see the big picture.

    Read the article

  • How to find an entry-level job after you already have a graduate degree?

    - by Uri
    Note: I asked this question in early 2009. A couple of months later, I found a great job. I've previously updated this question with some tips for whoever ends up in a similar situation, and now cleaned it up a little for the benefit of the fresh batch of graduates. Original post: In my early 20s I abandoned a great C++ development career path in a major company to go to graduate school and get a research masters (3 years). I did another year in industrial research, and then moved to the US to attend graduate school again, getting another masters and a Ph.D in software engineering from a top school (another 6 years down the drain). I was coding the whole way throughout my degrees (core Java and Eclipse plug-ins) and working on research related to software engineering (usability of APIs). I ended up graduating the year of the recession, with a son on the way and the prospects of no healthcare. Academic jobs and industrial research jobs are quite scarce. Initially, I was naive, thinking that with my background, I could easily find a coding job. Big mistake. It turns out that I'm in a complicated position. Entry level positions are usually offered to college undergraduates. I attended my school's career fairs, but you could immediately see signs of Ph.D. aversion and overqualification issues. Some of the recruiters I spoke with explicitly told me that they wanted 20 year olds with clean slates, and some were looking for interns since they are in various forms of hiring freezes. I managed to get a couple of interviews from these career fairs and through recruiters. However, since I've been out of school for a long time and programming primarily in Java, I am also no longer proficient in C/C++ and the usual range of college-level interview questions that everyone uses. I had no problems with this when I was 19 and interviewing for my first job since a lot of what you do in C is manipulate pointers and I was coding C++ for fun and for school. Later I was routinely doing pointer manipulation on the job, and during my first masters taught college courses with data structures and C++. But even though I remember many properties of C++ well, it's been close to ten years since I regularly used C++ and pointers. As a Java developer I rarely had to work at this level, but experience in OOD and in writing good maintainable code is meaningless for C++ interviews. Reading books as a refresh and looking at sample code did not do the trick. I also looked at mid-to-senior level Java positions, but most of them focused on J2EE APIs rather than on core Java and required a certain number of years in industrial positions. Coding research tools and prior C++ experience doesn't count. So that sends me back to entry-level jobs that are posted through job-boards, and these are not common (mostly they are Monster junk), and small companies are even less likely to answer a Ph.D. compared to the giants who participate in top-10 career fairs. Even worse, in many companies initial screening is done by HR folks who really don't want to deal with anything anomalous like a Ph.D. Any tips on how I should approach this intractable position? For example, what should I write in cover letters? Note that while immigration is not an issue for me, I cannot go freelance as I need the benefits (and in particular group health insurance). During my studies I had no time to contribute to open-source projects or maintain a popular blog, so even if I invested in that now there would be no immediate benefit. Updates: In the two months after posting this I received several offers to work as a core Java developer in the financial industry and accepted one from a firm where I am working to this day. For those who find themselves in similar situations, here are my tips: Give up on trying to find an entry level positions. You can't undo time. Accept the fact that there is Ph.D. discrimination in the job market (some might say rightfully so). It is legal to discriminate based on education. No point fighting it. The most important tip is to focus on the language you are comfortable with. The sad truth about programming in a particular language is that it is not like riding a bike. If you haven't used a language in the last few years, and can't actually apply it routinely (not just as a refresher) before you start your search, it is going to be very difficult to do well in an interview. Now that I'm interviewing others, I routinely see it in folks with a mixed C++/Java background. We maintain "a shadow" of the old language but end up with a weird mix that makes it hard to interview on either. Entry-level folks are at an advantage here since they usually have one language. Memory can help you do great in a screening interview, but without recent day-to-day experience, code tests will be difficult. Despite the supposed relation, core Java programming and J2EE programming are two different things with different skillsets. If you come from academia, you likely have very little J2EE experience and may find it hard to get accepted for a J2EE job. J2EE jobs seem to have a larger list of acronyms in their requirements. In addition, from interviewing J2EE developers it seems that for many there is a focus on mastering specific APIs and architectures, whereas core Java development tends to be secondary. In the same way that I can no longer manipulate pointers well, a J2EE developer may have difficulties doing low level Java manipulation. This puts you at a relative advantage in competing for core Java jobs! If you are able to work for startups (in terms of family life and stability) or migrate to startup-rich areas such as the west coast, you can find many exciting opportunities where advanced degrees are a benefit. I've since been approached by several startups, although I had to decline. Work through a recruiter if possible. They have direct contacts with the hiring parties, allowing you to "stand out". It is better to get a clear yes/no confirmation from a recruiter on whether a company might be interested in interviewing you, than it is to send your resume and hope that someone will ever see it. Recruiters are also a great way of bypassing HR. However, also beware of recruiters. They have a vested interest and will go to various shady practices and pressure tactics. To find a good recruiter, talk to a friend who declined a job offer he got through a recruiter. A good recruiter, to me, is measured in how they handle that. Interview for the jobs that require your core strength. If you're rusty or entirely unfamiliar with a technology around which the job revolves, you're probably not a good match. Yes, you probably have the talent to master them, but most companies would want "instant gratification". I got my offers from companies that wanted core Java developer. I didn't do well on places that wanted advance C++ because I am too rusty and not up to date on recent libraries. I also didn't hear from companies that wanted lots of J2EE experience, and that's ok. Finding companies that want core Java without web is harder, but exists in specific industries (e.g., finance, defense). This requires a lot more legwork in terms of search, but these jobs do exist. There are different interview styles. Some companies focus on puzzles, some companies focus on algorithms, and some companies focus on design and coding skills. I had the most success in places where the questions were the most related to the function I would have been performing. Pick companies accordingly as well.

    Read the article

< Previous Page | 946 947 948 949 950 951 952 953 954 955 956 957  | Next Page >